Method of recording data on a multi-layer recording medium, recording medium, and apparatus thereof

ABSTRACT

A method for recording data on a recording medium having one or more recording layers. The method includes reading control information having a plurality of control information units for controlling recording/reproducing of data from the recording medium. The control information unit includes an identifier of the recording layer to which the control information unit applies and a recording velocity applicable to the corresponding recording layer. A sequence of the information units is ordered according to the recording velocity and the recording layer identifier.

DOMESTIC PRIORITY INFORMATION

This is a continuation application of application Ser. No. 10/880,663filed Jul. 1, 2004, the entire contents of which are hereby incorporatedby reference.

FOREIGN PRIORITY INFORMATION

This application claims the benefit of the Korean Application No.10-2003-0046420 filed on Jul. 9, 2003, Korean Application No.10-2003-0063271 filed on Sep. 9, 2003, Korean Application No.10-2003-0063591 filed on Sep. 15, 2003, and Korean Application No.10-2003-0065628 filed on Sep. 22, 2003, which are hereby incorporated byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to recording media, and more particularly,to a method of recording disc control information on a recordableoptical disc including at least one recording layer, in which writingspeed information and per writing speed write strategy information(write strategy parameters) are included within the recorded disccontrol information, and to method of recording data using the disccontrol information recorded in a specific area of the recordableoptical disc.

2. Discussion of the Related Art

A high density optical recording medium, known as HD-DVD, is widely usedto record and store high-definition video data, large-amount programdata, and high-quality audio data and so on. The Blu-ray disc representsnext-generation HD-DVD technology. Technological specifications are nowbeing established for the global standardization of the Blu-ray disc,including standards for the write once Blu-ray disc (BD-WO). Meanwhile,a rewritable Blu-ray disc, known as the 1×-speed BD-RE and now beingdiscussed, should be compatible with BD-RE discs expected to have higherwriting speeds, i.e., the 2X-speed BD-RE and beyond. BD-WOspecifications for high writing speed are also in progress. Efficientsolutions for coping with the high writing speed of a high-densityoptical disc are Urgently needed, and the specifications establishedshould ensure mutual compatibility.

SUMMARY OF THE INVENTION

One exemplary embodiment relates to a method for recording data on arecording medium having one or more recording layers. The method callsfor reading control information including a plurality of controlinformation units for controlling recording/reproducing of data from therecording medium. The control information unit includes an identifier ofthe recording layer to which the control information unit applies and arecording velocity applicable to the corresponding recording layer. Asequence of the information units is ordered according to the recordingvelocity and the recording layer identifier.

Another exemplary embodiment relates to an apparatus for recording dataon a recording medium having one or more recording layers. The apparatushaving a pick-up part for reading control information including aplurality of control information units for controllingrecording/reproducing of data from the recording medium. The controlinformation unit includes an identifier of the recording layer to whichthe control information unit applies and a recording velocity applicableto the corresponding recording layer. A sequence of the informationunits is ordered according to the recording velocity and the recordinglayer identifier. A controller is used for controlling the recording ofthe data on the recording medium based on the read control information.

Another exemplary embodiment relates to a recording medium having one ormore recording layers. The recording medium having a data areaconfigured to record user data on each recording layer; and one or moremanagement area configured to record at least one control informationblock including a plurality of control information unit for controllingrecording/reproducing of the user data. The control information unitincluding an identifier of the recording layer to which the controlinformation unit applies and a recording velocity applicable to thecorresponding recording layer. A sequence of the information units isordered according to the recording velocity and the recording layeridentifier.

Additional advantages, objects, and features of the invention will beset forth in part in the description which follows and in part willbecome apparent to those having ordinary skill in the art uponexamination of the following or may be learned from practice of theinvention. The objectives and other advantages of the invention may berealized and attained by the structure particularly pointed out in thewritten description and claims hereof as well as the appended drawings.

It is to be understood that both the foregoing general description andthe following detailed description of the present invention areexemplary and explanatory and are intended to provide furtherexplanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this application, illustrate embodiment(s) of the invention andtogether with the description serve to explain the principle of theinvention. In the drawings:

FIG. 1 is a diagram of a single-layer disc applicable to the presentinvention;

FIG. 2 is a diagram of a dual-layer disc applicable to the presentinvention;

FIG. 3 is a diagram of a management area where disc control informationof the present invention is recorded, illustrating a disc informationrecording format;

FIG. 4 is a diagram of a sample data structure of disc controlinformation recorded according to a first embodiment of the presentinvention;

FIGS. 5A and 5B are diagrams of a sample configuration sequence of thedisc control information recorded according to the first embodiment ofthe present invention;

FIGS. 6A and 6B are exemplary diagrams of recording the disc controlinformation according to the first embodiment of the present invention;

FIGS. 7A-7C are other exemplary diagrams of recording the discinformation according to the first embodiment of the present invention;

FIG. 8 is a diagram of a sample data structure of disc controlinformation recorded according to a second embodiment of the presentinvention;

FIGS. 9A and 9B are exemplary diagrams of a configuration sequence ofthe disc control information recorded according to the second embodimentof present invention; and

FIG. 10 is a block diagram of an optical disc recording and reproducingapparatus according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts. Forconvenience of explanation, a Blu-ray disc (BD) is taken as an exampleof an optical disc according to the present invention. Yet, it isapparent that the concept of the present invention, which ischaracterized in an optical disc having its disc control informationrecorded thereon, is applicable to DVD-RAM/-RW/+RW/-R/+R and the likefor example in the same manner.

Besides, although terms used in the present invention are possiblyselected from the currently well-known ones, some terms are arbitrarilychosen by the applicant in some cases so that their meanings areexplained in detail in the following description. Hence, the presentinvention should be understood with the intended meanings of thecorresponding terms chosen by the applicant instead of the simple namesor meanings of the terms themselves.

First of all, ‘disc control information’ in the description of thepresent invention means an area including various information for discrecord playback or information for disc record playback. And, the disccontrol information is commonly designated information provided to aprerecorded area within a disc or to an embossed area for a disc user bya disc manufacturer. Yet, the disc control information is provided notonly to the prerecorded area but also to a recordable area. The discinformation within the prerecorded or embossed area can be copied to therecordable area as well. And, they are just exemplary.

For instance, the disc control information is called ‘disc information’in BD or ‘physical format information’ in DVD-RAM/-RW/+RW/-R/+R. Hence,it is apparent that the technical background of the present invention isidentically applicable to ‘physical format information’ inDVD-RAM/-RW/+RW/-R/+R. For convenience of explanation, ‘disc information(hereinafter abbreviated DI)’ corresponding to a case of Blu-ray disc(BD) is taken as an example.

FIG. 1 and FIG. 2 are structural diagrams of optical discs according tothe present invention, in which a recordable optical disc is enough tobe the optical disc applicable to the present invention. Moreover, therecordable disc can be any one of a rewritable optical disc, awrite-once optical disc, and the like.

FIG. 1 is a structural diagram of a single-layer disc having onerecording layer according to the present invention.

Referring to FIG. 1, a lead-in area is provided as a management area onan inner circumference area of an optical disc, whereas a lead-out areais provided as a management area on an outer circumference area of theoptical disc. Specifically, a prerecorded area and a rewritable orwrite-once area are separated from each other within the innercircumference area of the disc.

The prerecorded area is an area (called ‘embossed area’) where data wasalready written in manufacturing the disc, whereby a user or system isunable to perform data writing on the prerecorded area at all. InBD-RE/WO, the prerecorded area is named PIC (permanent information andcontrol data) area. And, the above-described disc information(hereinafter called ‘DI’) as information required for disc recording isrecorded in the PIC area.

In a data area, provided are a user data area where user's real data isrecorded and spare areas ISA and OSA to replace a generated defect area.Specifically, TDMA (temporary defect management area) for recordinginformation of defect and general managements is provided to such awrite-once optical disc as BD-WO. In case of the re-writable BD (BD-RE),TDMA is unnecessary so that such an area is left as a reserved area.

The present invention intends to provide a method of efficientlyrecording disc information (DI) as disc control information required forrecord playback of a disc in the prerecorded or recordable area. It isapparent that a recording method in the prerecorded area is differentlyapplied to each kind of discs. In case of BD-RE/WO, the PIC area as theprerecorded area is recorded by biphased high frequency modulatedsignals, the high frequency modulated signals in the corresponding areaare played back according to a specific playback method, and informationis acquired from the playback.

FIG. 2 is a diagram of a dual-layer disc having dual recording layers,in which a recording layer starting with a lead-in is named a firstrecording layer Layer0 and a recording layer ending with a lead-out isnamed a second recording layer Layer1.

In the dual-layer disc, the PIC area is provided to lead-in and lead-outareas of a disc inner circumference area, and disc information (DI) ofthe same contents is recorded in the PIC area.

FIG. 3 is a structural diagram of a PIC area in the disc shown in FIG. 1or FIG. 2. As mentioned in the foregoing description, it means thatinformation can be rearranged like the structure of the PIC area in FIG.3 when the entire information within the high frequency modulated PICarea is acquired.

A method of configuring disc information (DI) in the PIC area isexplained in detail as follows.

In BD-RE/WO, ‘one cluster’ represents a minimum record unit, fivehundred forty-four clusters gather to construct one fragment as oneupper record unit, and total five fragments gather to form the PIC area.Disc information is recorded in a front head cluster of a first fragmentIF0. The disc information is plurally recorded per recording layer andwriting speed permitted by the corresponding optical disc, and one discinformation includes one hundred twelve bytes. Specifically, discinformation constructed with 112-bytes is called disc information (DI)frame. Moreover, the same contents of the disc information arerepeatedly recorded in each front head cluster of the rest of thefragments, thereby enabling to cope with loss of the disc information.

Information representing the corresponding recording layer, informationrepresenting writing speed, and write strategy information correspondingto the writing speed are recorded within each disc information. Hence,such information is utilized in record playback of the correspondingoptical disc, thereby enabling to provide optimal recording power perrecording layer and per writing speed.

Namely, the disc information (DI) of the present invention ischaracterized in providing specific writing speed information supportedby the corresponding disc and associated write strategy information, andmore specifically, in providing specific writing speed supported foreach recording layer and associated write strategy information via aspecified method in case that a plurality of recording layers exist inthe corresponding disc.

And, the specific configuration of the disc information (DI) relates tothat of Blu-ray disc (BD). It is also apparent that a DVD based disc mayhave a configuration different from the above-explained structure.Specifically, if a size of disc information (DI) corresponds to that ofBD, it is 112-bytes equivalently for example. Yet, by regarding discinformation (DI) of the same recording layer as one information toprovide once without repeating common information, it may be able toconfigure the write strategy differing per writing speed only inaddition.

Various embodiments for a method of configuring disc information and amethod of recording specific information and the like within discinformation according to the present invention are explained in detailby referring to the attached drawings as follows.

FIGS. 4 to 7C are diagrams for a method of recording disc information ofan optical disc according to a first embodiment of the presentinvention, in which disc information is configured per writing speed andin which disc information is configured in a specific sequence perrecording layer within each corresponding writing speed.

FIG. 4 shows a concept of recording disc control information of anoptical disc according to a first embodiment of the present invention.

Referring to FIG. 4, a sequence for disc information each is decided bya sequence number and is recorded by 1-byte. For instance, theinformation is recorded in a 5^(th) byte within disc information, isnamed ‘DI frame sequence number in DI block’, and is briefly representedby ‘00h, 01h, 02h, . . . ’. Namely, if the information of the 5^(th)byte is ‘00h’, it means 1^(st) disc information. If the information ofthe 5^(th) byte is ‘07h’, it means 8^(th) disc information.

In configuring disc information, the present invention is characterizedin that disc information is separately provided per writing speed andper recording layer and that a configuration sequence of a plurality ofthe separately provided disc informations is uniformly decided accordingto a predetermined manner.

For instance, if a corresponding optical disc includes a pair ofrecoding layers and four kinds of applicable writing speeds (e.g., 1×speed, 2× speed, 3× speed, and 4× speed) exist, disc information can beconfigured in a following manner.

‘00h’ of 1^(st) disc information is related to 1× speed and 1^(st)recording layer L0. ‘01h’ of 2^(nd) disc information is related to 1×speed and 2^(nd) recording layer L1. ‘02h’ of 3^(rd) disc information isrelated to 2× speed and 1^(st) recording layer L0. ‘03h’ of 4^(th) discinformation is related to 2× speed and 2^(nd) recording layer L1. ‘04h’of 5^(th) disc information is related to 3× speed and 1^(st) recordinglayer L0. ‘05h’ of 6^(th) disc information is related to 3× speed and2^(nd) recording layer L1. ‘06h’ of 7^(th) disc information is relatedto 5× speed and 1^(st) recording layer L0. And, ‘07h’ of 8^(th) discinformation is related to 5× speed and 2^(nd) recording layer L1.

Namely, in configuring disc information, the present invention ischaracterized in that at least one disc information is configured perwriting speed and the respective per writing speed disc informations arereconfigured per recording layer. Hence, the writing speed is preferredin the sequence of configuring the disc informations to a recordinglayer type.

FIG. 5A exemplarily shows a method of configuring disc informationaccording the first embodiment of the present invention in FIG. 4, inwhich total sixteen disc informations are configured in case that fourkinds of applicable writing speeds (e.g., 1×, 2×, 4×, and 6×) and fourrecording layers (L0, L1, L2, and L3) exist within a disc.

Referring to FIG. 5A, 1 ^(st) to 4^(th) disc informations 00h to 03hbecome disc information for 1× speed, 5^(th) to 8^(th) disc informations04h to 07h become disc information for 2× speed, 9^(th) to 12^(th) discinformations 08h to 11h become disc information for 4× speed, and13^(th) to 16^(th) disc informations 02h to 15h become disc informationfor 6× speed.

And, per writing speed disc informations come into configuring separatedisc informations per recording layer to define as follows. Namely,‘00h’, ‘04h’, ‘08h’and ‘12h’ mean disc informations for “1” recordinglayer L0 at corresponding writing speeds, respectively. ‘01h’, ‘05h’,‘09h’, and ‘13h’ mean disc informations for 2^(nd) recording layer L1 atcorresponding writing speeds, respectively. ‘02h’, ‘06h’, ‘10h’, and‘14h’ mean disc informations for 3^(rd) recording layer L2 atcorresponding writing speeds, respectively. And, ‘03h’, ‘107h’, ‘11h’,and ‘15h’ mean disc informations for 4^(th) recording layer L3 atcorresponding writing speeds, respectively.

FIG. 5B exemplarily shows a method of configuring disc informationaccording the first embodiment of the present invention in FIG. 4, inwhich total eight disc informations are configured in case that fourkinds of applicable writing speeds (e.g., 1×, 2×, 4×, and 6×) and tworecording layers (L0, L1) exist within a disc.

The disc information configuring method in FIG. 5B is as good as that inFIG. 5A. First of al, per writing speed disc informations arepreferentially configured and then reconfigured per recording layer.

FIG. 6A and FIG. 6B are exemplary diagrams of recording the disc controlinformation according to the first embodiment of the present invention,in which intrinsic ‘recording layer information’ and ‘writing speedinformation’ are recorded within disc information.

Referring to FIG. 6A, ‘DI frame sequence number in DI block’ is providedto 5^(th) byte of each disc information to mean a sequence, which meansthat disc informations are configured in a specific sequence in the samemanner of FIG. 4. Besides, recording layer information and recordingvelocity information to be used for corresponding disc information arerepresented by specific bits to be provided to a specific area, e.g.,7^(th) byte, within the corresponding disc information each. Forinstance, the recording layer information and the recording velocityinformation are recorded in upper and lower 4-bits of the 7^(th) byte,respectively.

The recording layer information is defined as follows. First of all,‘000b’ of the recording layer information means 1^(st) recording layerL0. ‘0001b’ of the recording layer information means 2^(nd) recordinglayer L1. And, ‘1111b’ of the recording layer information means 16^(th)recording layer L115.

Meanwhile, the recording velocity information enables to define 4-bitsin various ways as follows. Namely, ‘0000b’, ‘0001b’, ‘0011b’, ‘0111b’,and ‘1111b’ are defined to mean 1× speed, 2× speed, 4× speed, 8× speed,and 16× speed, respectively.

Hence, the above-manners of defining the recording layer information andthe recording velocity information can be defined in various ways viaspecification establishment. For example, the recording layer orvelocity information can be defined by allocating 1-byte thereto.

Thus, the intrinsic recording layer and velocity informationscorresponding to its sequence number, as shown in FIG. 6A, are recordedin a previously promised specific location (7^(th) byte), whereby it isfacilitated to confirm the recording layer and velocity informations ofthe corresponding disc information. And, write power or write parametersfitting the recording layer and velocity are recorded in detail usingP^(th)˜111^(th) bytes, thereby enabling efficient record playback usingthe informations.

FIG. 6B shows an example of disc information including its intrinsicrecording layer information and recording velocity information, in whichtotal sixteen disc informations are configured in case that four kindsof applicable writing speeds (e.g., 1×, 2×, 4×, and 6×) and fourrecording layers (L0, L1, L2, and L3) exist within a disc.

The detailed configuring method of the disc information is the same inFIG. 5A. Considering the example in FIG. 6A, each of the discinformations includes its intrinsic recording layer information andrecording velocity information. For instance, upper 4-bits of 7^(th)byte within ‘02h’ of 3^(rd) disc information is set to ‘0010’ toindicate 3^(rd) recording layer L2 and lower 4-bits thereof is set to‘0000’ to indicate 1× speed, whereby it can be apparently representedthat the corresponding disc information relates to 1× speed and 3^(rd)recording layer.

For another instance, upper 4-bits of 7^(th) byte within ‘14h’ of15^(th) disc information is set to ‘0010’ to indicate 3^(rd) recordinglayer L2 and lower 4-bits thereof is set to ‘0101’ to indicate 1× speed,whereby it can be apparently represented that the corresponding discinformation relates to 6× speed and 3^(rd) recording layer.

FIGS. 7A to 7C are diagrams of an another example of recording discinformation according to the first embodiment of the present invention,in which ‘disc-applicable writing speed information’ and ‘recordinglayer information existing within disc’ are commonly recorded within thecorresponding disc.

Referring to FIG. 7A, ‘DI frame sequence number in DI block’ is providedto 5^(th) byte of each disc information to mean a sequence, which meansthat disc informations are configured in a specific sequence in the samemanner of FIG. 4. Besides, writing speed information applicable by acorresponding disc is recorded within a specific area (N^(th) byte)within disc, which is named ‘Writing speed flag’ field.

For instance, whether a specific writing speed of eight kinds of writingspeeds is applicable by the corresponding disc is represented by 1-biteach in the same area having 1-byte allocated thereto. Namely, it can bedefined that the corresponding writing speed is not applicable(supported) if a bit value is ‘0b’ in entire bits or that thecorresponding writing speed is applicable (supported) if the bit valueis ‘1b’. Hence, each of the bits b0˜b7 within 1-byte becomes flaginformation indicating presence or non-presence of applicability of aspecific writing speed. For instance, if 1× speed is applicable by acorresponding disc only, ‘0000 0001’ is written in N^(th) byte. If allof the eight kinds of writing speeds are applicable, ‘1111 1111’ iswritten in the N^(th) byte.

In the above explanation, 1× and 2× speeds utilized by every disc almostare previously decided to be adopted. Yet, writing speeds decided byspecification can be used as the rest writing speeds from 3^(rd) writingspeed. For instance, it is possible to set 3^(rd), 4^(th), 5^(th),6^(th), 7^(th), and 8^(th) writing speeds (3^(rd)×, 4^(th)×, 5^(th)×,6^(th)×, 7^(th)×, 8^(th)×) to 5×, 6×, 8×, 12×, 14×, and 16× speeds,respectively.

Meanwhile, recording layer information indicating the number ofrecording layer(s) existing within the corresponding disc is recorded inanother specific area (L^(th) byte) within the disc information, whichis named ‘Number of Recording Layer’ field. For instance, a valuemeaning the number of the recording layer(s) can be represented by abinary number in the same area having 1-byte allocated thereto. In casethat the recording layer is the single layer in FIG. 1, ‘0000 0001’ iswritten in the L^(th) byte. In case that the recording layer is the duallayer in FIG. 2, ‘0000 0010’ is written in the L^(th) byte. In case thatfour recording layers exist, ‘0000 0100’ is written in the L^(th) byte.

Since limitation is put on the number of the currently consideredrecording layer(s), which is currently two recording layers, 4-bitswithin the L^(th) byte are enough to represent total fifteen recordinglayers (in case of ‘1111’). In such a case, it is apparent that othervalid information can be written in the rest area (4-bits) of the L^(th)byte.

Moreover, identification information for identifying a kind of writestrategy (WS) recorded in P^(th)˜111^(th) bytes is written in anotherspecific area (M^(th) byte) within the disc information, which is named‘Write Strategy (WS) Type’ field.

Namely, in the disc information of the present invention, one writestrategy (WS) is recorded for a specific writing speed and a specificrecording layer and the write strategy is optionally selected fromvarious kinds of specified types by a disc manufacturer. Hence, if thecorresponding disc information is a first type write strategy WS−1,‘0000 0001’ is written in the M^(th) byte. If the corresponding discinformation is a second type write strategy WS2, ‘0000 0010’ is writtenin the M^(th) byte. And, substantial write strategy (WS) is recorded inP^(th)˜111^(th) bytes. Yet, the substantial write strategy (WS) will berecoded as a value interoperating with the decided write strategy (WS)type in the M^(th) byte. The write strategy (WS) type via the M^(th)byte is optionally recordable in every disc information. And, it is alsopossible to apply one specified write strategy (WS) type in 1× speeddisc information, which is expected to be supported by every recordplayback apparatus (FIG. 10), in a mandatory manner.

The detailed recording method of the write strategy (WS) is not a majorconcern of the present invention. Yet, in brief, a medium property of arecording layer is generally modified by applying a laser beam to therecording layer within an optical disc via a pickup (‘11’ in FIG. 10) toperform a recording thereof. Hence, it should be decided a strength(write power) of the laser beam, a time of applying the write powerthereto, and the like. The above-decided various kinds of writestrategies are named ‘Write Strategy (WS)’ in general and specificcontents recorded within a specific ‘Write Strategy (WS)’ are named‘Write Strategy (WS) parameters’.

And, the write strategy (WS) can be recorded in various ways. As a discbecomes to be highly densified and to run at higher speed, a writingspeed, i.e., disc RPM) as well as the medium property of the recordinglayer is considerably affected. Hence, a more accurate system isrequested. And, the various write strategies (WS) are explained asfollows for example.

First of all, there is a system having a recording pulse smaller by 1than a recording mark size (n) formed on a recording layer medium, whichmay be called ‘(n−1) WS’. Secondly, there is a system having a recordingpulse having a size amounting to a half of the recording mark size (n),which may be called ‘n/2 WS’. Besides, new write strategies (WS) keepbeing developed. Regarding the different kinds of write strategy (WS),when there exist the various systems of the write strategy (WS) exist asparameters applied to the write strategies (WS) differ from each other,a disc manufacturer tests the recording power according to the writestrategy (WS) recorded in the selected M^(th) byte and then records aresult of the test as write strategy (WS) in the Pth˜111^(th) byteswithin the disc information.

From the above-recorded ‘writing speed information’ in the N^(th) byteand the ‘recording layer information’ in the L^(th) byte, the recordplayback apparatus (FIG. 10) recognizes how many disc informations existwithin the corresponding disc. Namely, the number of the existing discinformations is found by multiplying an applicable writing speed numberby the number of recording layers.

As the present invention applies one write strategy (WS) for a specificwriting speed and a specific recording layer, the kind (type) and numberof the write strategy (WS) may not be taken into consideration indeciding the number of disc information(s). Yet, in a second embodimentof the present invention, it will be described that a plurality of writestrategies (WS) can exist for a specific writing speed and a specificrecording layer. In such a case, the total number of the existing discinformations is not always found by multiplying an applicable writingspeed number by the number of recording layers.

Hence, a sequence of a plurality of the above-decided disc informationsis decided by the sequence numbers, which is written in the 5^(th) bytein the foregoing description, and each of the disc informationsdesignates the previously decided writing speed and recording layer bythe sequence.

For example, by knowing that four writing speeds applicable by a discexist if the N^(th) byte is ‘0000 1111’ and that two recording layersexist within the disc if the L^(th) byte is ‘0000 0010’, total eightdisc informations are needed so that the sequence will be ‘00h˜07h’.And, it is previously decided that disc informations of ‘00h’, ‘01h’,‘02h’, ‘03h’, ‘04h’, ‘05h’, ‘06h’, and ‘07h’ relate to ‘1' speed, 1^(st)recording layer’, ‘2× speed, 2^(nd) recording layer’, ‘2× speed, 1^(st)recording layer’, ‘2×0 speed, 2^(nd) recording layer’, ‘3^(rd) writingspeed, 1^(st) recording layer’, ‘3^(rd) writing speed, 2^(nd) recordinglayer’, ‘4^(th) writing speed, 2^(nd) recording layer’, and ‘4^(th)writing speed, 2^(nd) recording layer’, respectively.

Hence, in order to acquire the disc information for a specific targetwriting speed and a specific target recording layer, the record playbackapparatus (FIG. 10) is facilitated to check which disc information isrelated to the specific target writing speed and recording layer from‘writing speed information’ of the N^(th) byte and ‘recording layerinformation’ of the L^(th) byte commonly recorded within the respectivedisc informations instead of playing back to check the entire discinformations.

FIG. 7B shows an example of recording disc information according to thefirst embodiment of the present invention in FIG. 7A. It can be knownthat there are two (1×, 2×) applicable writing speeds from N^(th) byte(‘0000 0010b’) commonly recorded in the entire disc informations andthat two recording layers exist within a disc from L^(th) byte (‘00000010b’).

Hence, in the example of FIG. 7B, total four disc informations (tworecording layers * two writing speeds) exist and a sequence of the discinformations becomes ‘00h’ (1×,L0)→‘01h’ (1×,L1)→‘02h’ (2×, L0)→‘03h’(2×, L1). This is done by a specified content according to apredetermined sequence. Thus, the entire disc informations should beconfigured according to the above manner to enable reciprocalcompatibility for utilization.

An intrinsic write strategy (WS) is recorded in other bytes within eachdisc information as well as N^(th) and L^(th) bytes. Specifically,information of a type of a write strategy (WS) written inP^(th)˜111^(th) bytes within the corresponding disc information isrecorded in M^(th) byte. Namely, informations in the M^(th) andp^(th)111^(th) bytes can differ in each disc information.

In the example in FIG. 7B, ‘00h’ (1×,L0) and ‘01h’ (1X,L1) relate to theapplication of a first type write strategy (WS−1) and ‘02h’ (2×,L0) and‘03h’ (2×,L1) relate to the application of a second type write strategy(WS−2).

FIG. 7C shows another example of recording disc information according tothe first embodiment of the present invention in FIG. 7A. It can beknown that there are eight (1×, 2×, . . . , 16×) applicable writingspeeds from N^(th) byte (‘1111 1111b’) commonly recorded in the entiredisc informations and that four recording layers exist within a discfrom L^(th) byte (‘0000 010b’).

Hence, in the another example of FIG. 7C, total thirty-two discinformations (four recording layers * eight writing speeds) exist and asequence of the disc informations becomes ‘00h’ (1×,L0)→‘01h’(1×,L1)→‘02h’ (1×,L2)→‘03h’ (1×,L4)→‘04h’ (2×,L0)→ . . . →‘31h’(16×,L4). This is done by a specified content according to apredetermined sequence. Thus, the entire disc informations should beconfigured according to the above manner to enable reciprocalcompatibility for utilization.

An intrinsic write strategy (WS) is recorded in other bytes within eachdisc information as well as N^(th) and L^(th) bytes. Specifically,information of a type of a write strategy (WS) written inP^(th)˜111^(th) bytes within the corresponding disc information isrecorded in M^(th) byte. Namely, informations in the M^(th) andP^(th)˜111^(th) bytes can differ in each disc information.

In the another example of FIG. 7C, if a record playback unit (FIG. 10)intends to search disc information related to 2× speed (2×,L0) of afirst recording layer to perform recording by applying a write strategy(WS) within the corresponding disc information, it can be known from theinformations in the N^(th) and L^(th) bytes commonly recorded in theentire disc informations that total thirty-two disc informations (fourrecording layers * eight writing speeds) exist in the corresponding discaccording to the sequence of the disc informations such as ‘00h’(1×,L0)→‘01h’ (1×,L1)→‘02h’ (1×,L2)→‘03h’ (1×,L4)→‘04h’ (2×,L0)→ . . .→‘31h’ (16×,L4). Hence, the record playback apparatus (FIG. 10) enablesto recognize that the disc information related to the 2' speed (2×,L0)of the first recording layer to be searched is ‘04h’ and that thecorresponding disc information (‘04h’) is recorded as the first typewrite strategy (WS−1) from the write strategy (WS) type identificationinformation (‘0000 0001b’) recorded in the M^(th) byte within thecorresponding information (‘04h’), thereby reading out parameter valuesof the first type write strategy (WS−1) via the P^(th)˜111^(th) bytes toutilize in the recording.

Likewise, if intending to search disc information related to 16× speed(16×,L3) of a fourth recording layer to perform recording by applying awrite strategy (WS) within the corresponding disc information, therecord playback unit (FIG. 10) recognizes that the corresponding discinformation is ‘31h’ via the same process and that the write strategytype (WS) is the second type (WS−2), thereby enabling to utilize them inthe recording.

FIGS. 8 to 9B shows a method of recording dist information of an opticaldisc according to a second embodiment of the present invention, which isextended from the first embodiment of the present invention in FIG. 4.The second embodiment of the present invention is characterized in thatdisc information is configured per writing speed, disc information isconfigured per recording layer within the corresponding writing speed,and at least one write strategy (WS) is configured for each discinformation per corresponding recording layer.

FIG. 8 shows a concept of the method of recording disc information ofthe optical disc according to the second embodiment of the presentinvention.

Referring to FIG. 8, a sequence for disc information each is decided bya sequence number and is recorded by 1-byte.

For instance, the information is recorded in a 5^(th) byte within discinformation, is named ‘DI’ frame sequence number in ‘DI block’, and isbriefly represented by ‘00h, 01h, 02h, . . . ’. Namely, if theinformation of the 5^(th) byte is ‘00h’, it means 1^(st) discinformation. If the information of the 5^(th) byte is ‘07h’, it means8^(th) disc information.

In configuring disc information, the present invention is characterizedin that disc information is separately provided per writing speed andper recording layer and that a configuration sequence of a plurality ofthe separately provided disc informations is uniformly decided accordingto a predetermined manner.

For instance, if a corresponding optical disc includes a pair ofrecoding layers and plural kinds of applicable writing speeds exist,disc information can be configured in a following manner.

‘00h’ of 1^(st) disc information is related to 1× speed, 1^(st)recording layer L0, and WS1. ‘01h’ of 2^(nd) disc information is relatedto 1× speed, 1^(st) recording layer L0, and WS2. ‘02h’ of 3^(rd) discinformation is related to 1× speed, 2^(nd) recording layer L1, and WS 1.‘03h’ of 4^(th) disc information is related to 1× speed, 2^(nd)recording layer L1, and WS2. ‘04h’ of 5^(th)disc information is relatedto 2× speed, 1^(st) recording layer L0, and WS1. ‘05h’ of 6^(th) discinformation is related to 2× speed and 1^(st) recording layer L0, andWS3. ‘06h’ of 7^(th) disc information is related to 2× speed, 2^(nd)recording layer L1, and WS1. And, ‘07h’ of 8^(th) disc information isrelated to 2× speed, 2^(nd) recording layer L1, and WS3.

Namely, in configuring disc information, the second embodiment accordingto the s present invention is characterized in that at least one discinformation is configured per writing speed, the respective per writingspeed disc informations are reconfigured per recording layer, and atleast one WS type is provided to each recording layer.

Hence, the writing speed, the recording layer, and the WS type are takeninto consideration in order of priority in configuring the discinformations.

FIG. 9A exemplarily shows a method of configuring disc informationaccording the second embodiment of the present invention in FIG. 8, inwhich total sixteen disc informations are configured in case that fourkinds of applicable writing speeds (e.g., 1×, 2×, 4×, and 6×) and fourrecording layers (L0, L1, L2, and L3) exist within a disc.

Referring to FIG. 9A, ‘DI frame sequence number in DI block’ is providedto 5^(th) byte of each disc information to mean a sequence, which meansthat disc informations are configured in a specific order (writing speed→recording layer →WS type) of priority in FIG. 8. Besides, writing speedinformation applicable by a corresponding disc is recorded within aspecific area (N^(th) byte) within disc, which is named ‘Writing speedflag’ field. For instance, whether a specific writing speed of eightkinds of writing speeds is applicable by the corresponding disc isrepresented by 1-bit each in the same area having 1-byte allocatedthereto.

Namely, it can be defined that the corresponding writing speed is notapplicable (supported) if a bit value is ‘0b’ in entire bits or that thecorresponding writing speed is applicable (supported) if the bit valueis ‘1b’. Hence, each of the bits b0˜b7 within 1-byte becomes flaginformation indicating presence or non-presence of applicability of aspecific writing speed. For instance, if 1× speed is applicable by acorresponding disc only, ‘0000 0001’ is written in N^(th) byte. If allof the eight kinds of writing speeds are applicable, ‘1111 1111’ iswritten in the N^(th) byte. In the drawing, ‘0000 0111b’ is written inthe N^(th) byte to allow 1^(st) to 3^(rd) writing speeds.

In the above explanation, 1× and 2× speeds utilized by every disc almostare previously decided to be adopted. Yet, writing speeds decided byspecification can be used as the rest writing speeds from 3^(rd) writingspeed. For instance, it is possible to set 3^(rd), 4^(th), 5^(th),6^(th), 7^(th), and 8^(th) writing speeds (3^(rd) X, 4^(th) X, 5^(th) X,6^(th) X, 7^(th) X, 8^(th) X) to 4×, 6×, 8×, 12×, 14×, and 16× speeds,respectively.

And, information of informing a kind of write strategy (WS) applicableby a specification of a corresponding disc is recorded in anotherspecific area (L^(th) byte) within the disc information, which is named‘Write Strategy (WS) flag’ field. For instance, whether a specific writestrategy (WS) of eight kinds of write strategies (WS) is applicable bythe corresponding disc is represented by 1-bit each in the same areahaving 1-byte allocated thereto. Namely, it can be defined that thecorresponding write strategy (WS) is not applicable (supported) if a bitvalue is ‘0b’ in entire bits or that the corresponding write strategy(WS) is applicable (supported) if the bit value is ‘1b’. Hence, each ofthe bits b0˜b7 within 1-byte becomes flag information indicatingapplicability of a specific write strategy (WS). For instance, if 1^(st)to 3^(rd) type write strategies WS1 to WS3 are applicable by acorresponding disc only, ‘0000 0111b’ is written in L^(th) byte. If allof the eight types of write strategies (WS 1 to WS8) are applicable,‘1111 1111b’ is written in the L^(th) byte. In the drawing, ‘0000 1111b’is written in the L^(th) byte to indicate that four WS types WS1 to WS4are applicable.

Moreover, recording layer information indicating the number of recordinglayer(s) existing within the corresponding disc is recorded in anotherspecific area (M^(th) byte) within the disc information, which is named‘Number of Recording Layer’ field. For instance, a value meaning thenumber of the recording layer(s) can be represented by a binary numberin the same area having 1-byte allocated thereto. In case that therecording layer is the single layer (one recoding layer) in FIG. 1,‘0000 0001b’ is written in the M^(th) byte. In case that the recordinglayer is the dual layer (two recording layers) in FIG. 2, ‘0000 0010b’is written in the M^(th) byte. In case that four recording layers exist,‘0000 0100b’ is written in the M^(th) byte.

Besides, parameters of a selected write strategy (WS) are written inanother specific area (P^(th)˜111^(th) bytes) within the discinformation, which is named ‘Write Strategy (WS) parameters’ field.

By writing the N^(th), L^(th), and M^(th) byte informations recordedwithin the disc information by the same values in common to the entiredisc informations, respectively, the record playback apparatus (FIG. 10)is facilitated to acquire the informations of the writing speedapplicable by the corresponding disc, the write strategy (WS) kind, andthe number of the recording layers despite playing back any discinformation.

Specifically, it may be able to record disc information per writingspeed, per recording layer, and per write strategy (WS) type. Yet, insuch a case, the number of the recorded disc informations excessivelyincreases. Moreover, a disc manufacturer should test the entire writestrategy (WS) types and record the test results within the discinformation, whereby it becomes a burden.

Therefore, in the embodiment according to the present invention, writestrategies (WS) of which number (m) is smaller than that (n) of themaximum applicable write strategy types are recordable within discinformation and a disc manufacturer further enables to optionally recorda specific one of a plurality of write strategies (WS), whereby discmanufacturer's convenience is secured as well as an efficient recordingof disc information is enabled.

In FIG. 9A, recording is performed at 1× speed (1×) using 1^(st) and2^(nd) type write strategies WS1 and WS2, at 2× speed (2×) using 2^(nd)and 3^(rd) type write strategies WS2 and WS3, or at 3^(rd) writing speed(3×) using 3^(rd) and 4^(th) type write strategies WS3 and WS4.

Namely, it is able to record disc information using write strategy (WS)types (two types) less than total applicable write strategy (WS) types(four types) per writing speed.

FIG. 9B shows another example of recording disc information according tothe second embodiment of the present invention in FIG. 8. Like FIG. 9A,three kinds of applicable writing speeds exist and ‘00000111b’ iswritten in N^(th) byte. Four applicable write strategy types exist and‘00001111b’ is written in L^(th) byte. And, two recording layers existwithin a disc and ‘000000010b’ is written in M^(th) byte.

Specifically, in configuring disc information using one of a pluralityof applicable write strategies (WS), at least one disc information isconfigured per the same writing speed and recording layer. In doing so,the most preferentially provided disc information is defined aspreferred WS provided by a disc manufacturer and another discinformation following the preferred WS is defined as alternative WS.

Namely, both disc information ‘00h’ and disc information ‘01h’ relate to1× speed (1×) and 1^(st) recording layer (L0). Yet, the WS1 typeinformation recorded in ‘00h’ as preferentially provided discinformation becomes the preferred WS and the WS1 type informationrecorded in ‘01h’ as a next provided one becomes the alternative WS.

And, disc information ‘04h’, disc information ‘05h’, and discinformation ‘06h’ relate to 2× speed (2×) and 1^(st) recording layer(L0). Yet, the WS2 type information recorded in ‘04h’ as preferentiallyprovided disc information becomes the preferred WS, and the WS1 typeinformation recorded in ‘05h’ and the WS3 type information recorded in‘06h’ as next provided ones become the alternative WSs, respectively.Namely, they can be applied to at least three disc informations of thesame writing speed/recording layer.

Moreover, disc information ‘10h’ relates to 3^(rd) speed (3^(rd) X) and1^(st) recording layer (L0) and disc information ‘11h’ relates to 3^(rd)speed (3^(rd) X) and 2^(nd) recording layer (L0). In case that only oneWS type information is provided to the same writing speed/recordinglayer, the provided WS becomes the preferred WS.

Namely, when a disc manufacturer provides disc information within a discaccording to the previously determined specification, an optical recordplayback apparatus (FIG. 10) reads out the disc information in aspecific order (writing speed→recording layer). If a plurality of discinformations exist on the same writing speed/recording layer, theoptical record playback apparatus (FIG. 10) recognizes thepreferentially provided WS within the disc information as the preferredWS and the next WS as the alternative WS additionally provided by a discmanufacturer, thereby enabling record playback using disc informationefficiently.

FIG. 10 is a block diagram of an optical disc record playback accordingto the present invention.

Referring to FIG. 10, a record playback apparatus according to thepresent invention includes a record playback unit 10 carrying out recordplayback on an optical disc and a control unit 20 controlling the recordplayback unit 10.

The control unit 20 gives a record or playback command for a specificarea, and the record playback unit 10 caries out the record/playback forthe specific area according to the command of the control unit 20.Specifically, the record playback unit 10 includes an interface unit 12performing communications with an external device, a pickup unit 11directly recording data on the optical disc or playing back the data, adata processor 13 receiving a playback signal from the pickup unit 11 torestore into a necessary signal value or modulating to deliver a signalto be recorded into a signal to be recorded on the optical disc, a servounit 14 reading out a signal from the optical disc correctly orcontrolling the pickup unit 11 to record a signal on the optical disccorrectly, a memory 15 temporarily storing disc control informationincluding disc control information, and a microcomputer 16 responsiblefor controlling the above-described elements within the record playbackunit 10.

A recording process of an optical disc according to the presentinvention is explained in detail as follows.

First of all, once an optical disc is loaded in the optical recordplayback apparatus, the entire disc management information within thedisc is read out to be temporarily stored in the memory 15 of the recordplayback unit 10. And, various kinds of the disc management informationare utilized for the record/playback of the optical disc. Specifically,the management information stored in the memory 15 includes disc controlinformation of the present invention. Hence, the recording layerinformation, writing speed information, and write strategy fitting thecorresponding writing speed recorded within the disc information areread out to be stored in the memory.

If intending to perform a recording on a specific area within theoptical disc, the control unit 20 renders such an intent into a writingcommand and then delivers it to the record playback unit 10 togetherwith data for writing location information to be recorded. Afterreceiving the writing command, the microcomputer 16 decides thecorresponding writing speed applied to an intended recording layerwithin the optical disc from the management informations stored in thememory 15 and then performs the writing command using the optimal writestrategy by referring to the decided writing speed.

Specifically, in case that the recording is performed on the opticaldisc by the present invention, the disc information as managementinformation is provided in a specific order and the microcomputer 16recognizes which WS is the preferred WS of the disc manufacturer in thesame writing speed/recording layer. Therefore, it is more facilitated toperform the recording on a specific recoding layer within an opticaldisc at a specific writing speed.

Accordingly, the present invention provides various methods of providingdisc control information coping with higher writing speed in ahigh-density optical disc, thereby enabling to uniformly apply thestandardized disc control information to efficiently cope with therecord/playback of the optical disc.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present invention. Thus,it is intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

1. A computer-readable medium comprising: a specific area of thecomputer-readable medium storing control information for controllingrecording of data on each of the more than one recording layer of thecomputer-readable medium, the control information including informationunits in sequential order, each information unit including writestrategy information usable at a writing speed applicable to a recordinglayer of the computer-readable medium, the sequential order of at leastone information units being by order of increasing writing speed amongthe information units, and for a same writing speed, the sequentialorder of the at least one information unit being by order of ascendingrecording layer number among the information units.
 2. Thecomputer-readable medium of claim 1, wherein the write strategyinformation includes write strategy parameters corresponding torecording power value and pulse timing value usable at the writing speedapplicable to the recording layer during recording of the data.
 3. Thecomputer-readable medium of claim 2, wherein the specific area islocated in a specific recording layer of the computer-readable medium.4. The computer-readable medium of claim 3, wherein the specific area isa sub-area of a lead-in area included in the specific recording layer.5. The computer-readable medium of claim 4, wherein the controlinformation is pre-recorded or embossed information in the sub-area ofthe lead-in area.
 6. The computer-readable medium of claim 5, whereinthe pre-recorded or embossed control information is copied to arecordable area of the computer-readable medium.
 7. Thecomputer-readable medium of claim 6, wherein the computer-readablemedium is a recordable DVD disc including at least two recording layers.8. The computer-readable medium of claim 5, wherein the write strategyinformation further includes write strategy type information indicatingone of n−1 write strategy type and n/2 write strategy type where n is alength of mark and each type represents a number of write pulses to forma corresponding mark.
 9. The computer-readable medium of claim 8,wherein the n−1 write strategy type includes a different writeparameters than that of the n/2 write strategy type.
 10. Thecomputer-readable medium of claim 9, wherein the computer-readablemedium is a recordable Blu-ray Disc including at least two recordinglayers.
 11. An apparatus for recording data on a recording mediumincluding at least two recording layers, comprising: an optical pickupconfigured to read control information including information units froma specific area of one of the recording layers of the recording mediumand configured to record the control information on a recordable area ofthe recording medium, each information unit including write strategyinformation usable at a writing speed applicable to one of the recordinglayers; and a controller, operatively coupled to the optical pickup,configured to control the optical pickup to record the information unitsin sequential order, the sequential order of at least one informationunits by order of increasing writing speed among the information units,and for a same writing speed, the sequential order of the at least oneinformation units being by order of ascending recording layer numberamong the information units.
 12. The apparatus of claim 11, wherein thecontrol information is pre-recorded or embossed information and islocated in a sub-area of a lead-in area of the recording medium; and theoptical pickup is configured to read the pre-recorded or embossedcontrol information.
 13. The apparatus of claim 12, wherein the writestrategy information includes write strategy parameters corresponding torecording power value and pulse timing value usable at the writing speedapplicable to the recording layer and the optical pickup is configuredto read the control information including the write strategy parameters.14. An apparatus for recording data on a recording medium including atleast two recording layers, comprising: an optical pickup configured toread or write data from or on the recording medium; a servo, operativelycoupled to the optical pickup, configured to control a servo operationof the optical pickup according to a writing speed; a memory configuredto store control information, the control information including writestrategy information usable at a writing speed applicable to one of therecording layers; and a controller operatively coupled to the opticalpickup, servo and memory, the controller configured to identify thecontrol information stored in the memory and control the optical pickupto record the data on the recording medium by using the write strategyinformation included in the identified control information, the controlinformation including a plurality of information units in a sequentialorder, each information unit including the write strategy information,and the sequential order of at least one information unite being byorder of increasing writing speed, and for a same writing speed amongthe information units, the sequential order of the at least oneinformation units being by order of ascending recording layer numberamong the information units.
 15. The apparatus of claim 14, wherein thememory stores the control information read by the optical pickup. 16.The apparatus of claim 14, wherein the write strategy informationincludes write strategy parameters corresponding to recording powervalue and pulse timing value usable at the writing speed applicable tothe recording layer; and the controller is configured to control theoptical pickup to record the data by using the write strategy parametersincluded in the write strategy information.
 17. The apparatus of claim16, wherein the controller is further configured to check a writestrategy type based on write strategy type information indicating one ofn−1 write strategy type and n/2 write strategy type where n is a lengthof mark and each type represents a number of write pulses to form acorresponding mark, the n−1 write strategy type including differentwrite parameters than that of the n/2 write strategy type; and thecontroller configured to read write strategy parameters corresponding tothe write strategy type and control the recording of data by using thewrite strategy parameters.
 18. A method for recording data on arecording medium including at least two recording layers, the methodcomprising: reading control information including information units froma specific area of one of the recording layers of the recording medium,each information unit including writing strategy information usable at awriting speed applicable to one of the recording layers; and recordingthe read at least one information units in sequential order on arecordable area of the recording medium, the sequential order of the atleast one information units being by order of increasing writing speed,and for a same writing speed among the information units, the sequentialorder of the at least one information units being by order of ascendingrecording layer number among the information units.
 19. The method ofclaim 18, wherein the reading step reads the control information from asub-area of a lead-in area of the recording medium, the controlinformation being pre-recorded or embossed information in the sub-area.20. The method of claim 19, wherein the write strategy informationincludes write strategy parameters corresponding to recording powervalue and pulse timing value usable at the writing speed applicable tothe recording layer during recording of the data.
 21. A method forrecording data on a recording medium including at least two recordinglayers, the method comprising: reading control information includinginformation units in sequential order from a specific area of one of therecording layers of the recording medium, each information unitincluding write strategy information usable at a writing speedapplicable to one of the recording layers, the sequential order of atleast one information units being by order of increasing writing speedamong the information units, and for a same writing speed, thesequential order of the at least one information units being by order ofascending recording layer number among the information units; andrecording the data on the recording medium by using the write strategyinformation included in the control information.
 22. The method of claim21, wherein the reading step reads the control information from asub-area of a lead-in area of the recording medium.
 23. The method ofclaim 22, further comprising: reading write strategy type informationwhich is included in the control information and indicates one of n−1write strategy type and n/2 write strategy type where n is a length ofmark and each type represents a number of write pulses to form acorresponding mark, the n−1 write strategy type including a differentwrite parameters than that of the n/2 write strategy type.
 24. Themethod of claim 22, wherein the recording step records the data on auser data area of the recording medium by using write strategyparameters included in the write strategy information, the writestrategy parameters corresponding to recording power value and pulsetiming value usable at the writing speed applicable to the recordinglayer.
 25. The computer-readable medium of claim 1, comprising: an L0recording layer and an L1 recording layer; and wherein the sequentialorder of information units is by order of increasing writing speed, andfor a same writing speed, the sequential order of information units isby the L0 recording layer and then by the L1 recording layer.
 26. Amethod for recording data on a recording medium including at least tworecording layers, comprising: storing control information, the controlinformation including write strategy information usable at a writingspeed applicable to one of the recording layers, the control informationincluding a plurality of information units in a sequential order, eachinformation unit including the write strategy information, and thesequential order of at least one information unite being by order ofincreasing writing speed among the information units, and for a samewriting speed, the sequential order of the at least one informationunite being by order of ascending recording layer number among theinformation units; and recording data on the recording medium by usingthe stored control information.